import os
import subprocess
import sys


def _install_bundled_deps() -> None:
    """Install transformers from bundled wheels (eval sandbox has no PyPI access)."""
    wheels_dir = os.path.join(os.path.dirname(os.path.abspath(__file__)), "wheels")
    if not os.path.isdir(wheels_dir):
        return
    subprocess.run(
        [
            sys.executable,
            "-m",
            "pip",
            "install",
            "-q",
            "--no-index",
            f"--find-links={wheels_dir}",
            "transformers==4.56.2",
        ],
        check=True,
    )


_install_bundled_deps()

import re
import csv
import json
import shutil
import tempfile
import torch
from transformers import AutoTokenizer, AutoModelForCausalLM

# The repo is the working directory at run time, and there is no network.
os.environ["HF_HUB_OFFLINE"] = "1"
os.environ["TRANSFORMERS_OFFLINE"] = "1"
MODEL_ID = "."
MAX_NEW_TOKENS = 2000
TEMPERATURE = 0.8
TOP_P = 0.95
MAX_ATTEMPTS = 5
SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
PROMPTS_DIR = os.path.join(SCRIPT_DIR, "prompts")


def load_tokenizer(model_id: str = "."):
    """Load tokenizer, converting tokenizer.json for older tokenizers if needed."""
    tokenizer_path = os.path.join(model_id, "tokenizer.json")
    with open(tokenizer_path, encoding="utf-8") as handle:
        data = json.load(handle)

    merges = data.get("model", {}).get("merges", [])
    if not merges or not isinstance(merges[0], list):
        return AutoTokenizer.from_pretrained(model_id)

    # Older tokenizers expect merge pairs as "a b" strings, not ["a", "b"] lists.
    data["model"]["merges"] = [" ".join(piece) for piece in merges]
    tmpdir = tempfile.mkdtemp()
    for name in ("tokenizer_config.json", "special_tokens_map.json"):
        src = os.path.join(model_id, name)
        if os.path.isfile(src):
            shutil.copy(src, tmpdir)
    with open(os.path.join(tmpdir, "tokenizer.json"), "w", encoding="utf-8") as handle:
        json.dump(data, handle)
    return AutoTokenizer.from_pretrained(tmpdir)


# Short durable contract only — task-specific procedure is loaded into the user turn.
SYSTEM = (
    "You solve International Linguistics Olympiad (IOL) problems using only the "
    "CONTEXT and QUERY you are given. Do not rely on prior knowledge of the language.\n"
    "Always end with a line that says exactly `FINAL ANSWERS:`, then one bare answer "
    "per line for each QUERY item, in order — no numbering, quotes, or extra text."
)

KNOWN_TASK_TYPES = (
    "translation",
    "fill_blanks",
    "match_letters",
    "text_to_num",
    "num_to_text",
)


def _prompt_path(task_type: str) -> str:
    """Resolve prompts/<task_type>.txt, falling back to prompts/default.txt."""
    # Keep basename-only to avoid path traversal if task_type is ever untrusted.
    safe = os.path.basename(task_type.strip())
    candidate = os.path.join(PROMPTS_DIR, f"{safe}.txt")
    if safe in KNOWN_TASK_TYPES and os.path.isfile(candidate):
        return candidate
    default = os.path.join(PROMPTS_DIR, "default.txt")
    if os.path.isfile(default):
        return default
    raise FileNotFoundError(
        f"No prompt template for task_type={task_type!r} under {PROMPTS_DIR}"
    )


def load_user_prompt_template(task_type: str) -> str:
    with open(_prompt_path(task_type), encoding="utf-8") as handle:
        return handle.read()


def build_user_prompt(context: str, task_type: str, query: str) -> str:
    """Load the task-type-specific user template and fill in this example."""
    template = load_user_prompt_template(task_type)
    return template.format(
        context=context.strip(),
        query=query.strip(),
        task_type=task_type.strip(),
    )


# Prefer a dedicated header line; also allow same-line answers after the colon.
FINAL_ANSWERS_LINE_RE = re.compile(
    r"(?im)^[^\w\n]*final answers?[^\w\n]*:?[ \t]*(?=\n|$)|"
    r"(?im)^[^\w\n]*final answers?\s*:\s*"
)
FINAL_ANSWERS_INLINE_RE = re.compile(
    r"(?is)\bfinal answers?\s*:\s*"
)


def extract_raw_final(text: str) -> str:
    """Return text after the last final-answers marker, or '' if none found."""
    line_matches = list(FINAL_ANSWERS_LINE_RE.finditer(text))
    if line_matches:
        return text[line_matches[-1].end() :]

    inline_matches = list(FINAL_ANSWERS_INLINE_RE.finditer(text))
    if inline_matches:
        return text[inline_matches[-1].end() :]

    return ""


def expected_answer_count(query: str, task_type: str) -> int:
    if task_type == "match_letters":
        numbered = re.findall(r"^\s*\d+\.", query, re.MULTILINE)
        return len(numbered) or 1

    if "blanks" in query.lower():
        range_match = re.search(r"\((\d+)-(\d+)\)", query)
        if range_match:
            return int(range_match.group(2)) - int(range_match.group(1)) + 1
        return len(re.findall(r"\(\d+\)", query)) or 1

    numbered = re.findall(r"^\s*\d+[.)]", query, re.MULTILINE)
    return len(numbered) or 1


def split_single_line_answer(text: str, expected: int, task_type: str) -> list[str]:
    text = text.strip()
    if expected <= 1:
        return [text]

    def try_split(pattern: str) -> list[str] | None:
        parts = [part.strip() for part in re.split(pattern, text) if part.strip()]
        return parts if len(parts) == expected else None

    if task_type == "match_letters":
        for pattern in (r"\s+", r",\s*", r";\s*"):
            if result := try_split(pattern):
                return result
        letters = re.findall(r"[A-Za-z]", text)
        if len(letters) == expected:
            return [letter.upper() for letter in letters]
        return [text]

    if task_type in ("text_to_num", "num_to_text"):
        for pattern in (r",\s*", r";\s*", r"\s+"):
            if result := try_split(pattern):
                return result
        return [text]

    for pattern in (r";\s*", r",\s*"):
        if result := try_split(pattern):
            return result
    return [text]


def parse_answer_lines(text_after_marker: str, query: str, task_type: str) -> list[str]:
    """Parse cleaned answer lines from the raw final-answers section."""
    answers = []
    for line in text_after_marker.splitlines():
        stripped_line = line.strip("`").strip()
        if stripped_line == "":
            continue

        match_numbered_prefix = re.match(r"^\s*\d+[.)]\s+(.*)", stripped_line)
        if match_numbered_prefix:
            cleaned_line = match_numbered_prefix.group(1).strip()
        else:
            cleaned_line = stripped_line

        cleaned_line = re.sub(r"\*\*", "", cleaned_line).strip()

        if task_type == "match_letters":
            parts = [
                part.strip("().[]")
                for part in re.split(r"[\s,;]+", cleaned_line)
                if part.strip()
            ]
            if not (
                len(parts) > 1
                and all(re.fullmatch(r"[A-Za-z]", part) for part in parts)
            ):
                match_letter_word = re.match(
                    r"^\s*(?:\(([A-Za-z])\)|\[([A-Za-z])\]|([A-Za-z]))\.?:?\s*(.*)$",
                    cleaned_line,
                )
                if match_letter_word:
                    letter = (
                        match_letter_word.group(1)
                        or match_letter_word.group(2)
                        or match_letter_word.group(3)
                    )
                    cleaned_line = letter.upper()

        if cleaned_line:
            answers.append(cleaned_line)

    expected = expected_answer_count(query, task_type)
    if len(answers) == 1 and expected > 1:
        answers = split_single_line_answer(answers[0], expected, task_type)
    return answers


def postprocess_answer(text, query, task_type):
    """Keep only the content after the last 'FINAL ANSWERS' marker."""
    text_after_marker = extract_raw_final(text)
    if not text_after_marker.strip():
        return []
    return parse_answer_lines(text_after_marker, query, task_type)


tok = load_tokenizer(MODEL_ID)
model = AutoModelForCausalLM.from_pretrained(
    MODEL_ID, torch_dtype=torch.float16, device_map="auto"
).eval()

with open("/tmp/data/test.csv", encoding="utf-8", newline="") as f:
    test_rows = list(csv.DictReader(f))

outputs_queries_types = []
for r in test_rows:
    user_prompt = build_user_prompt(r["context"], r["task_type"], r["query"])
    print(f"id={r['id']} task_type={r['task_type']} template={os.path.basename(_prompt_path(r['task_type']))}", flush=True)
    messages = [
        {"role": "system", "content": SYSTEM},
        {"role": "user", "content": user_prompt},
    ]
    ids = tok.apply_chat_template(
        messages, add_generation_prompt=True, return_tensors="pt",
    ).to(model.device)

    done = False
    attempts = 0
    text = ""
    while not done and attempts < MAX_ATTEMPTS:
        with torch.no_grad():
            out = model.generate(
                ids,
                max_new_tokens=MAX_NEW_TOKENS,
                do_sample=True,
                temperature=TEMPERATURE,
                top_p=TOP_P,
            )
        text = tok.decode(out[0][ids.shape[-1] :], skip_special_tokens=True).strip()
        attempts += 1
        if extract_raw_final(text).strip():
            done = True
        else:
            print(f"TRYING AGAIN...attempts #{attempts}/{MAX_ATTEMPTS}", flush=True)

    outputs_queries_types.append((text, r["id"], r["query"], r["task_type"]))
    print(f"{len(outputs_queries_types)}/{len(test_rows)} done", flush=True)

rows = []
for answer, row_id, query, task_type in outputs_queries_types:
    answers = postprocess_answer(answer, query, task_type)
    rows.append({"id": row_id, "pred": json.dumps(answers, ensure_ascii=False)})
with open("submission.csv", "w", encoding="utf-8", newline="") as f:
    writer = csv.DictWriter(f, fieldnames=["id", "pred"])
    writer.writeheader()
    writer.writerows(rows)
print("wrote submission.csv", flush=True)